Conduit module coupled with heating or cooling module

ABSTRACT

A heating and cooling system for use with hot, cold and source fluid circuits. A conduit module couples a heating/cooling module with the fluid circuits. The conduit module includes four three-way valves to communicated fluid from and to the fluid circuits to first and second heat exchangers in the heating/cooling module. The first heat exchanger is used to heat a fluid flow and the second one chills a second fluid flow. The conduit module simultaneously supplies a hot fluid flow to a hot fluid circuit and a cold fluid to a cold fluid circuit. The source fluid is routed by the conduit module. A method of circulating fluid is also disclosed.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.15/410,659, filed Jan. 19, 2017, which is a divisional of U.S.application Ser. No. 14/094,465, filed on Dec. 2, 2013, which claims thebenefit of U.S. Provisional Application No. 61/732,871, filed on Dec. 3,2012. These applications are incorporated herein by reference in theirentirety.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to heating and cooling systems andconveying fluids in such heating and cooling systems.

2. Description of the Related Art

The use of heat pumps and geothermal fluid circuits to provide heatingand cooling in a building is known. Improvements in the efficientutilization and simplifications in the fluid flow controls of suchheating and cooling systems, however, remain desirable.

SUMMARY OF THE INVENTION

The present invention provides a conduit module that efficientlyutilizes the output of a heating/cooling module with a limited number ofvalves.

The invention comprises, in one form thereof, a conduit module adaptedto couple a heating/cooling module having first and second heatexchangers with a hot fluid circuit, a cold fluid circuit and a sourcefluid circuit. The conduit module includes a hot fluid supply conduitadapted to communicate fluid to the hot fluid circuit and a hot fluidreturn conduit adapted to receive fluid from the hot fluid circuit; acold fluid supply conduit adapted to communicate fluid to the cold fluidcircuit and a cold fluid return conduit adapted to receive fluid fromthe cold fluid circuit; and a source fluid supply conduit adapted tocommunicate fluid to the source fluid circuit and a source fluid returnconduit adapted to receive fluid from the source fluid circuit. Theconduit module also includes a first inlet conduit adapted to conveyfluid from the conduit module to the first heat exchanger and a firstoutlet conduit adapted to convey fluid from the first heat exchanger tothe conduit module wherein the first heat exchanger is adapted to heatthe fluid being conveyed by the first inlet and first outlet conduits;and a second inlet conduit adapted to convey fluid from the conduitmodule to the second heat exchanger and a second outlet conduit adaptedto convey fluid from the second heat exchanger to the conduit modulewherein the second heat exchanger is adapted to chill the fluid beingconveyed by the second inlet and second outlet conduits. The conduitmodule further includes four three-way valves. A first three-way valveis operably coupled with the hot fluid return conduit, the source fluidreturn conduit and the first inlet conduit; a second three-way valveoperably coupled with the first outlet conduit, the hot fluid supplyconduit and the source fluid supply conduit; a third three-way valveoperably coupled with the cold fluid return conduit, the source fluidreturn conduit and the second inlet conduit; and a fourth three-wayvalve operably coupled with the second outlet conduit, the cold fluidsupply conduit and the source fluid supply conduit.

The invention comprises, in another form thereof, a heating and coolingsystem adapted to be coupled with a hot fluid circuit, a cold fluidcircuit and a source fluid circuit. The system includes aheating/cooling module having a first heat exchanger and a second heatexchanger and a conduit module. The conduit module includes a hot fluidsupply conduit adapted to communicate fluid to the hot fluid circuit anda hot fluid return conduit adapted to receive fluid from the hot fluidcircuit; a cold fluid supply conduit adapted to communicate fluid to thecold fluid circuit and a cold fluid return conduit adapted to receivefluid from the cold fluid circuit; and a source fluid supply conduitadapted to communicate fluid to the source fluid circuit and a sourcefluid return conduit adapted to receive fluid from the source fluidcircuit. The conduit module also includes a first inlet conduit adaptedto convey fluid from the conduit module to the first heat exchanger anda first outlet conduit adapted to convey fluid from the first heatexchanger to the conduit module wherein the first heat exchanger isadapted to heat the fluid being conveyed by the first inlet and firstoutlet conduits; and a second inlet conduit adapted to convey fluid fromthe conduit module to the second heat exchanger and a second outletconduit adapted to convey fluid from the second heat exchanger to theconduit module wherein the second heat exchanger is adapted to chill thefluid being conveyed by the second inlet and second outlet conduits. Theconduit module further includes four three-way valves. A first three-wayvalve is operably coupled with the hot fluid return conduit, the sourcefluid return conduit and the first inlet conduit; a second three-wayvalve operably coupled with the first outlet conduit, the hot fluidsupply conduit and the source fluid supply conduit; a third three-wayvalve operably coupled with the cold fluid return conduit, the sourcefluid return conduit and the second inlet conduit; and a fourththree-way valve operably coupled with the second outlet conduit, thecold fluid supply conduit and the source fluid supply conduit.

In some embodiments, the heating/cooling module takes the form of a heatpump having a compressor, an evaporator, an expansion valve and acondenser coupled together to circulate a refrigerant therein in astandard refrigeration cycle and wherein the first heat exchangerdefines the condenser and the second heat exchanger defines theevaporator. 100081 The conduit module is advantageously adapted tosimultaneously supply heated fluid via the hot fluid supply conduit tothe hot fluid circuit and supply chilled fluid via the cold fluid supplyconduit to the cold fluid circuit.

Some embodiments, include at least one controller that controls theoperation of the first, second, third and fourth valves wherebyselective control of the valves defines a plurality of differentoperating modes. The plurality of operating modes advantageouslyincludes a primary heating with some cooling mode and a primary coolingwith some heating mode. The conduit module may be a modular standaloneunit installable separate from the heating/cooling unit.

The invention comprises, in another form thereof, a method ofcirculating fluid to a hot fluid circuit, a cold fluid circuit and asource fluid circuit. The method includes providing a heating/coolingmodule with a first heat exchanger and a second heat exchanger. Themethod also includes providing a conduit module with a plurality ofthree way valves wherein the conduit module is in fluid communicationwith the hot fluid circuit to communicate a hot fluid supply flow andreceive a hot fluid return flow; the conduit module is also in fluidcommunication with the cold fluid circuit to communicate a cold fluidsupply flow and receive a cold fluid return flow; and the conduit moduleis also in fluid communication with the source fluid circuit tocommunicate a source fluid supply flow and receive a source fluid returnflow. The conduit module is coupled with the heating/cooling modulewherein a first fluid flow is directed from the conduit module to thefirst heat exchanger to heat the first fluid flow and is then directedback to the conduit module and at least a portion of the first fluidflow is then communicated to the hot fluid circuit to define at least aportion of the hot fluid supply flow; and wherein a second fluid flow isdirected from the conduit module to the second heat exchanger to chillthe second fluid flow and is then directed back to the conduit moduleand at least a portion of the second fluid flow is then communicated tothe cold fluid circuit to define at least a portion of the cold fluidsupply flow. Fluid received by the conduit module from the source fluidcircuit is at least partially communicated to at least one of the hotfluid and cold fluid circuits to define at least a portion of one of thehot fluid supply flow and the cold fluid supply flow.

In some embodiments of the method, the plurality of three-way valvesincludes first, second, third and fourth valves, the first valvecontrollably receiving fluid from the hot fluid return flow and thesource fluid return flow and distributing fluid to the first fluid flow;the second valve controllably receiving fluid from the first fluid flowand distributing fluid to the hot fluid supply flow and the source fluidsupply flow, the first heat exchanger being operably disposed betweenthe first and second valves; the third valve controllably receivingfluid from the cold fluid return flow and the source fluid return flowand distributing fluid to the second fluid flow; the fourth valvecontrollably receiving fluid from the second fluid flow and distributingfluid to the cold fluid supply flow and the source fluid supply flow,the second heat exchanger being operably disposed between the third andfourth valves.

BRIEF DESCRIPTION OF THE DRAWINGS

The above mentioned and other features of this invention, and the mannerof attaining them, will become more apparent and the invention itselfwill be better understood by reference to the following description ofan embodiment of the invention taken in conjunction with theaccompanying drawings, wherein:

FIG. 1 is a schematic view of a heating and cooling system for abuilding.

FIG. 2 is a schematic view of a conduit module and heating/coolingmodule.

FIG. 3 is a schematic view of a heating/cooling module.

Corresponding reference characters indicate corresponding partsthroughout the several views. Although the exemplification set outherein illustrates an embodiment of the invention, the embodimentdisclosed below is not intended to be exhaustive or to be construed aslimiting the scope of the invention to the precise form disclosed.

DETAILED DESCRIPTION OF THE INVENTION

A heating and cooling system 10 is schematically depicted in FIG. 1. Inthis exemplary embodiment, a fluid is distributed to and from a building12 to provide heating and/or cooling. A conduit module 100 regulates theflow of fluid between building 12 and heating and cooling module 150.Fluid is returned from building 12 to conduit module 100 through returnlines 18. Fluid flows from conduit module 100 to heating/cooling module150 through inlet lines 22 and returns to conduit module 100 throughoutlet lines 24. The heating/cooling fluid is supplied to building 12through supply lines 20. The fluid is then used for heating and/orcooling purposes within building 12 or in some alternative applicationrequiring heating and/or cooling.

It is noted that while FIG. 1 illustrates a building 12 as receiving thedistributed fluids for heating and/or cooling purposes, it is notnecessary for the fluids to be distributed to an enclosed structure noris it necessary for the fluids to be used for heating or cooling ambientair. For example, the disclosed system will find many applications inindustrial settings where heating and/or cooling is needed forindustrial processing loads and the heating and cooling loads discussedherein may be either ambient air heating and cooling loads, industrialprocessing loads or some other type of heating and/or cooling load andthese loads may be referred to herein simply as heating or coolingloads.

The illustrated conduit module 100 can be used to provide heating,cooling or simultaneous heating and cooling without reversingrefrigeration flow direction in heating/cooling module 150. Conduitmodule 100 can be coupled with a heat pump as depicted in FIGS. 1-3 orcan be coupled with a chiller, heat recovery unit, or other suitableheating and/or cooling unit. Conduit module 100 is a standalone unitthat can be installed remotely from the heating/cooling module 150.Conduit module 100 may advantageously be a modular standalone unitinstallable separate from the heating/cooling unit.

FIG. 2 depicts a conduit module 100 and heating/cooling module 150 ingreater detail than FIG. 1. Conduit module 100 couples heating/coolingmodule 150 with a hot fluid circuit 103, a cold fluid circuit 107 and asource fluid circuit 111. Hot fluid circuit 103 circulates hot fluidfrom conduit module 100 to a building or other location requiringheating via hot fluid supply line 104 and returns the fluid to conduitmodule 100 via warm fluid return line 102. Cold fluid circuit 107circulates cold fluid from conduit module 100 to a building or otherlocation requiring cooling via cold fluid supply line 108 and returnsthe fluid to conduit module 100 via cool fluid return line 106. Sourcefluid circuit 111 circulates a thermal transfer source fluid to conduitmodule 100 from a thermal sink or heating/cooling source, such as ageothermal circuit, via inlet line 110 and returns the fluid to thethermal sink or heating/cooling source via outlet line 112. Source fluidcircuit 111 may advantageously take the form of a heat sink reservoirsuch as a geothermal well field, cooling tower, pond, lake or other formof thermal reservoir.

It is noted that the fluid circulated through circuit 111, as well asthe other fluid circuits 103, 107, is advantageously a heat transferfluid such as a propylene glycol and water mixture or other suitableheat transfer fluids. The use of such heat transfer fluids in geothermalloop fields and other thermal reservoir fluid circuits is well known inthe art.

Fluid lines 102, 104, 106, 108, 110 and 112 may advantageously take theform of headers thereby facilitating the connection of additional linesin addition to the line connected with conduit module 100. Conduitmodule 100 may include internal headers which connect with externalconduits or rely on external headers. As used herein, the term conduitmay also refer to a header and when elements 102, 104, 106, 108, 110 and112 are referred to herein as conduits or other similar term, theseelements and other elements referred to as a conduit or similar term maytake the form of a header. It is further noted that return lines 18 ofFIG. 1 correspond to fluid lines 102, 106 and 110 of FIG. 2 and thatsupply lines 20 of FIG. 1 correspond to fluid lines 104, 108 and 112 ofFIG. 2.

In the embodiment of FIG. 2, heating/cooling module 150 includes a heatexchanger 152 in the form of a condenser and a heat exchanger 154 in theform of an evaporator. Fluid is conveyed to heat exchanger 152 fromconduit module 100 via condenser inlet fluid conduit 116 and is conveyedback to conduit module 100 via condenser outlet fluid conduit 118. Fluidis conveyed to heat exchanger 154 from conduit module 100 via evaporatorinlet fluid conduit 124 and is conveyed back to conduit module 100 viaevaporator outlet fluid conduit 126. It is noted that inlet lines 22 ofFIG. 1 correspond to inlet conduits 116 and 124 in FIG. 2. Similarly,outlet lines 24 of FIG. 1 correspond to outlet conduits 118 and 126 ofFIG. 2.

When heating/cooling module 150 is operating, fluid passing throughcondenser 152 from inlet conduit 116 to outlet conduit 118 will pick upthermal energy. In other words, the fluid in outlet conduit 118 will behotter than the fluid in inlet conduit 116. Similarly, fluid passingthrough evaporator 154 from inlet conduit 124 to outlet conduit 126 willbe chilled. In other words, fluid in outlet 126 will be at a lowertemperature than fluid in inlet 124.

FIG. 3 illustrates one example of a heating/cooling module 150 ingreater detail. In this exemplary embodiment, module 150 employs astandard refrigeration cycle. As will be understood by those havingordinary skill in the art, a refrigerant vapor is compressed bycompressor 210 which increases both the pressure and temperature of therefrigerant. The high pressure and temperature refrigerant is then,conveyed through condenser 152 where thermal energy is transferred fromthe refrigerant to the fluid being conveyed from inlet conduit 116 tooutlet conduit 118. The refrigerant is converted from a vapor to aliquid in condenser 152 by the transfer of thermal energy. As can beseen in FIG. 3, condenser 152 may use a counter-flow configuration toenhance the transfer of thermal energy from the refrigerant to the fluiddischarged through outlet conduit 118.

The refrigerant flows from condenser 152 through expansion valve 218which reduces the pressure of the refrigerant resulting a liquid vapormixture. The refrigerant is fully converted back into a vapor inevaporator 154 whereby the fluid being conveyed from inlet conduit 124to outlet conduit 126 is cooled. Refigerant line 208 conveys therefrigerant vapor from evaporator 154 to compressor 210 and the cycle isrepeated. As can be seen in FIG. 3, evaporator 154 may use acounter-flow configuration to enhance the transfer of thermal energybetween the fluid entering through inlet conduit 124 and therefrigerant.

It is noted that heating/cooling module 150 is a heat pump as that termis used herein. More specifically, the term heat pump is used herein torefer to a system having two heat exchangers and employing a standardrefrigeration cycle. In this regard, it is further noted that somemarket segments employ the term heat pump only when referencing a systemhaving a reversing valve that allows each of two heat exchangers tooperate selectively as an evaporator or condenser and uses the termchiller or heat recovering chiller to refer to systems which have adedicated evaporator and a dedicated condenser. The term heat pump asused herein refers to both types of systems, i.e., systems with areversing valve and those without, and both types of systems, and othersystems which generate heated and/or chilled fluid, can be used with theconduit module 100 described herein.

Conduit module 100 couples heating/cooling module 150 with a hot fluidcircuit 103, a cold fluid circuit 107 and a source fluid circuit 111 andvalves 130, 132, 134, 136 control the distribution of hot and cold fluidstreams. In the illustrated embodiment, valves 130, 132, 134, 136 areall three-way valves having a conventional structure.

As will be recognized by those having ordinary skill in the art, theoperation of valves 130, 132, 134, 136 as well as the operation ofmodule 150 can be controlled by electronic controllers. For example, aunitary controller 302 can be used to control the operation of conduitmodule 100, its valves 130, 132, 134, 136 and its associated components,another unitary controller 304 can be used to control the operation ofheating/cooling module 150 and its associated refrigeration cycle andsafeties with a supervisory controller 300 managing the integration ofthe two module along with other associated modules in the overallsystem.

Turning now to the hot fluid circuit, first valve 130 receives fluidflow from conduit 114 which returns fluid to module 100 from hot fluidcircuit 103. Valve 130 also receives fluid from source fluid circuit 111from conduit 110. Fluid entering valve 130 is conveyed to condenserinlet conduit 116 which conveys the fluid to condenser 152 where it isheated. Hot fluid from condenser 152 is conveyed to second valve 132 bycondenser outlet conduit 118. Second valve 132 controllably distributesthe hot fluid to conduit 120 which conveys fluid to hot fluid circuit103 and conduit 112 which conveys fluid to source fluid circuit 111.Valves 130, 132 are used to control the distribution of fluid flow amongthese circuits.

Turning next, to the cold fluid circuit, third valve 134 receives fluidflow from conduit 122 which returns fluid to module 100 from cold fluidcircuit 107. Valve 134 also receives fluid from source fluid circuit 111from conduit 110. Fluid entering valve 134 is conveyed to evaporatorinlet conduit 124 which conveys the fluid to evaporator 154 where it iscooled. Cold fluid from evaporator 154 is conveyed to fourth valve 136by evaporator outlet conduit 126. Fourth valve 136 controllablydistributes the cold fluid to conduit 128 which conveys fluid to coldfluid circuit 107 and conduit 112 which conveys fluid to source fluidcircuit 111. Valves 134, 136 are used to control the distribution offluid flow among these circuits.

The use of three-way valves 130, 132, 134, 136 not only provides aconduit module with simplified valving, piping and control, it alsoprovides enhanced flexibility in fluid distribution thereby facilitatingenergy efficient utilization of heating/cooling module 150 and sourcefluid circuit 111. Oftentimes, heat pumps such as the illustratedheating/cooling module 150 are used for both heating and coolingpurposes but only for one of those purposes at any one time. Conduitmodule 100 allows heating/cooling module 150 to be used for both heatingand cooling purposes simultaneously. In other words, it allows forutilizing the energy from both the evaporator and the condenser insteadof just one or the other.

One difficulty in utilizing the energy from both the evaporator and thecondenser of a heat pump is that the heating and cooling loads which arebeing addressed are rarely balanced. In other words, the heat pump mustbe operated to meet the greater demand, either heating or cooling, andthere will be an excess capacity for the other load. The illustratedconduit module allows for the heat pump to efficiently and preciselymeet both demands even when the heating and cooling loads areunbalanced. This is accomplished by using valves 130, 132, 134, 136 toproportion the fluid flow to simultaneously meet both demands andthereby provide optimal utilization and the energy efficient managementof heating/cooling module 150.

Conduit module 100 and associated heating/cooling module 150 defineseveral different modes of operation to provide heating and coolingcapacities to a building. Such modes include a heating mode, a coolingmode, simultaneous heating and cooling, primary heating with somecooling and primary cooling with some heating.

In one mode or arrangement, fluid entering warm fluid header 102 isconveyed to conduit 114 and then to valve 130. The fluid is dischargedfrom valve 130 into conduit 116 which conveys the fluid to heatexchanger 152 in module 150 where the fluid is heated. The hot fluid isthen conveyed from heat exchanger 152 to valve 132 by conduit 118. Thehot fluid then enters conduit 120 which conveys it to hot fluid header104 where it can be used in hot fluid circuit 103. In this heating modearrangement all of the hot fluid is conveyed to hot fluid header 104 foruse in hot fluid circuit 103.

If there is no cooling demand, heat will still need to be transferredwithin evaporator 154 for the proper operation of heating/cooling module150. This can be accomplished by using a fan to blow air acrossevaporator 154 or by circulating source fluid from circuit 111 throughevaporator 154. More specifically, fluid may be conveyed from header 110through valve 134, and conduit 124 to evaporator 154. The fluid is thenconveyed from evaporator 154 by conduit 126 to valve 136 where it isdischarged to header 112 and returns to source fluid circuit 111, forexample, a geothermal heat sink.

In another arrangement or mode of operation for conduit module 100 andheating/cooling module 150, fluid from cool fluid header 106 is conveyedthrough conduit 122 to valve 134. Valve 134 routes the fluid to conduit124 which conveys it to heat exchanger 154 where the fluid is chilled.The now cold fluid is conveyed by conduit 126 out of module 150 to valve136. Valve 136 then routes the fluid to cold fluid header 108 whereby itcan be utilized in cold fluid circuit 107. In this cooling modearrangement all of the cold fluid is conveyed to cold fluid header 108for use in cold fluid circuit 107.

If there is no heating demand, heat will still need to be transferredwithin condenser 152 for the proper operation of heating/cooling module150. This can be accomplished by using a fan to blow air acrosscondenser 152 or by circulating source fluid from circuit 111 throughcondenser 152. More specifically, fluid may be conveyed from header 110through valve 130, and conduit 116 to condensor 152. The fluid is thenconveyed from evaporator 152 by conduit 118 to valve 132 where it isdischarged to header 112 and returns to source fluid circuit 111, forexample, a geothermal heat sink.

There may be situations where source fluid circuit 111 can be used toprovide free stage heating or cooling wherein the source fluid can becirculated for either heating or cooling purposes without operatingheating/cooling module 150.

For example, if the fluid entering source fluid header 110 issufficiently cold to address the cooling demands of cold fluid circuit107, fluid from header 110 can be conveyed to conduit 124 through valve134. It can pass through evaporator 154 and then to conduit 124. Becausemodule 150 is not operating, there will be no transfer of thermal energywith the fluid as it passes through evaporator 154. Conduit 126 willthen transfer the fluid to valve 136 which will direct it to conduit 128and cold fluid header 108 thereby allowing it be utilized in cold fluidcircuit 107. [0041] Similarly, when the fluid entering source fluidheader 110 is sufficiently warm to address the heating demands of hotfluid circuit 103, fluid from header 110 can be conveyed to conduit 116through valve 130. The fluid will then pass through condenser 152 and onto conduit 118. Because module 150 is not operating, there will be notransfer of thermal energy with the fluid as it passes through condenser152. Conduit 118 will then transfer the fluid to valve 132 which willdirect it to conduit 120 and hot fluid header 104 thereby allowing it beutilized in hot fluid circuit 103.

Fluid from source fluid circuit 111 can also be used to reduce the loadon heating/cooling module 150. As mentioned above, source fluid circuit111 may take the form of a heat sink reservoir such as a geothermal wellfield, cooling tower, pond, lake or other form of thermal reservoir. Forexample, fluid from a geothermal circuit can be admixed or blended witha colder fluid stream to increase the temperature of the fluid streambefore heating the blended fluid stream to thereby increase the overallefficiency of the unit and decrease the work and lift of therefrigeration cycle. For example, when heating is required and the fluidentering conduit module 100 from the source fluid circuit 111 is warmerthan the fluid returned to the conduit module from hot fluid circuit103, the fluid that is directed to heat exchanger 152 by valve 130advantageously includes fluid from source fluid circuit 111 and may beeither all fluid from source fluid return conduit 110 or a combinationof fluid from source fluid return conduit 110 and fluid from hot fluidcircuit return conduit 102.

Similarly, fluid from source fluid circuit 111 can be used when coolingis required. For example, when fluid from circuit 111 is cooler than thefluid being returned to conduit module 100 from cold fluid circuit 107,the fluid that is directed to heat exchanger 154 by valve 134advantageously includes fluid from source fluid circuit 111 and may beeither all fluid from source fluid return conduit 110 or a combinationof fluid from source fluid return conduit 110 and fluid from cold fluidcircuit return conduit 106.

It is noted that to provide a combined discharge three-way valves 130,134, which each have two inlets and one outlet, may be operated bysimultaneously allowing some incoming flow from both of the inlets anddischarging the combined fluid to the outlet, or, by periodicallyswitching from one inlet to the other to thereby provide for a combinedflow discharge. Similarly, to separate an inflow into two outflows,three-way valves 132, 136, which each have one inlet and two outlets,may be operated by allowing the incoming flow to be divided bysimultaneously discharging fluid through the two outlets, or, byperiodically switching the entire outflow from one outlet to the otheroutlet.

As mentioned above, when both heating and cooling are required, theheating and cooling demands may be unbalanced. In such a situation, thesource fluid circuit can be used as described above to efficiently meetthe greater demand, for example, by combining fluid from the sourcefluid circuit 111 with fluid being returned from the hot fluid circuitwhen the greater demand is a heating demand, and not using the sourcefluid circuit to increase the efficiency of the other demand. Therelative proportions of the source fluid and return fluid can beadjusted to account for the specific demands being placed on the system.

In some instances, the secondary or lesser demand side of the system maystill have excess capacity after using the source fluid circuit toenhance the efficiency of the greater demand side. In such situation,the source fluid circuit can be used to absorb the excess capacity ofthe lesser demand side. For example, if cooling demand is the primary orgreater demand and the fluid returned to conduit module 100 from thecold fluid circuit 107 is warmer than the fluid returned to the conduitmodule 100 from the source fluid circuit 111, fluid from circuit 111 maybe used to increase the efficiency of module 150 in meeting the coolingdemands of the system by blending fluid from both source fluid returnconduit 110 and cold circuit return conduit 106 before chilling thecombined fluid stream in heat exchanger 154 and then supplying thechilled fluid to cold fluid circuit 107. To absorb the excess heatcapacity of heat exchanger 152, fluid from source fluid return conduit110 may be used alone or in combination with fluid from hot fluid returnconduit 104 to absorb heat from heat exchanger 152. Alternatively, oradditionally, the hot fluid flowing from heat exchanger 152 to valve 132may be partially distributed to source fluid circuit 111 to therebyabsorb some of the excess heat capacity.

Such measures may also be used without combining return flow from thesource fluid circuit with the return flow from the primary demand sideof the system. For example, if the primary demand is a heating demand,fluid from the hot fluid return conduit 102 may be routed to heatexchanger 152 by valve 130 where it is heated and then returned to hotfluid circuit 103 by valve 132 without any fluid being interchanged withsource fluid circuit 111. On the other side of the system, if the fluidreturning from cold fluid circuit 107 is colder than the fluid returningfrom source fluid circuit 111, valve 134 may combine fluid from the coldfluid return conduit 106 with fluid from source fluid return conduit 110and then direct the combined flow to heat exchanger 154 which chills thecombined flow. Some or all of the chilled flow from heat exchanger 154can then be routed to cold fluid circuit 107 by valve 136.

The use of valves 130, 132, 134 and 136 to selectively distribute fluidflow between fluid circuits 103, 107, 111 may employed in various othermodes as well as those explicitly discussed herein as will be recognizedby those having ordinary skill in the art. Moreover, if module 150 isprovided with a reversing valve, even further flexibility in theoperation of the system can be obtained. However, one advantage ofmodule 100 is that it provides great flexibility in the operation of thesystem without the use of a reversing valve in module 150. [0049] Theuse of three-way valves 130, 132, 134, 136 provides a highly versatileconduit module with a limited number of valves and associated piping. Asmentioned above, the conduit module 100 may also be advantageouslyconfigured as a modular standalone unit installable separate from theheating/cooling unit. For example, valves 130, 132, 134, 136 and theirassociated piping could be mounted on a frame together with controller302. This module could then be positioned proximate a heating/coolingmodule and piping interconnections made between conduit module 100 andmodule 150 and fluid circuits 103, 107 and 111. Such a module structurefacilitates installation and maintenance and allows conduit module 100to be more readily installed in a preexisting system already having aheating/cooling module 150 and fluid circuits 103, 107 and 111.

While this invention has been described as having an exemplary design,the present invention may be further modified within the spirit andscope of this disclosure. This application is therefore intended tocover any variations, uses, or adaptations of the invention using itsgeneral principles.

What is claimed is:
 1. A conduit module to couple a plurality of fluidcircuits to a heating/cooling module having first and second heatexchangers, the conduit module comprising: first, second, and thirdsupply conduits to convey fluid to first, second, and source fluidcircuits, respectively, wherein the first supply conduit is configuredto convey fluid to the first fluid circuit for a heating load and thesecond supply conduit is configured to convey fluid to the second fluidcircuit for a cooling load; first, second, and third return conduits toreceive fluid from the first, second, and source fluid circuits,respectively; and first, second, third, and fourth three-way valves,wherein the first three-way valve is connected to the first returnconduit and the third return conduit, wherein the first three-way valveselectively regulates flow of fluid from the first return conduit andthe third return conduit to the first heat exchanger, the secondthree-way valve is connected to the first supply conduit and the thirdsupply conduit, wherein the second three-way valve selectively regulatesflow of fluid from the first heat exchanger to the first supply conduitand the third supply conduit for selective distribution to the firstfluid circuit and the source fluid circuit, the third three-way valve isconnected to the second return conduit and the third return conduit,wherein the third three-way valve selectively regulates flow of fluidfrom the second return conduit and the third return conduit to thesecond heat exchanger, and the fourth three-way valve is connected tothe second supply conduit and the third supply conduit, wherein thefourth three-way valve selectively regulates flow of fluid from thesecond heat exchanger to the second supply conduit and the third supplyconduit for selective distribution to the second fluid circuit and thesource fluid circuit.
 2. The conduit module of claim 1, including theheating/cooling module, and the heating/cooling module comprises a heatpump.
 3. The conduit module of claim 2, wherein the heating/coolingmodule excludes a reversing valve, and the conduit module and theheating/cooling module define a plurality of different heating andcooling operating modes.
 4. The conduit module of claim 3, wherein theplurality of different heating and cooling operating modes includes aheating mode, a cooling mode, and a simultaneous heating and coolingmode.
 5. The conduit module of claim 3, Wherein the plurality ofdifferent heating and cooling operating modes includes a primary heatingwith some cooling mode and a primary cooling with some heating mode. 6.The conduit module of claim 2, wherein the conduit module is a modularstand-alone unit installable separately from the heating/cooling module.7. The conduit module of claim 1, wherein the conduit module is adaptedto simultaneously convey heated fluid via the first supply conduit foruse in the first fluid circuit and convey chilled fluid via the secondfluid supply conduit for use in the second fluid circuit.
 8. The conduitmodule of claim 1, including a controller configured to selectivelyregulate fluid flow by each of the first, second, third, and fourththree-way valves.
 9. The conduit module of claim 1, including a firstinlet conduit adapted to convey fluid from the conduit module to thefirst heat exchanger, and a first outlet conduit adapted to convey fluidfrom the first heat exchanger to the conduit module, the first heatexchanger being adapted to heat or pass through unheated any fluid beingconveyed by the first inlet and first outlet conduits.
 10. The conduitmodule of claim 1, including a second inlet conduit adapted to conveyfluid from the conduit module to the second heat exchanger, and a secondoutlet conduit adapted to convey fluid from the second heat exchanger tothe conduit module, the second heat exchanger being adapted to chill orpass through unchilled any fluid being conveyed by the second inlet andsecond outlet conduits.
 11. The conduit module of claim 1, wherein thesecond three-way valve is configured to receive fluid heated by thefirst heat exchanger when the first heat exchanger is operating andfluid unheated by the first heat exchanger when the first heat exchangeris not operating.
 12. The conduit module of claim 1, wherein the fourththree-way valve is configured to receive fluid cooled by the second heatexchanger When the second heat exchanger is operating and fluid uncooledby the second heat exchanger when the second heat exchanger is notoperating.
 13. A modular conduit and valve apparatus to couple aplurality of fluid circuits to a heating/cooling apparatus having firstand second heat exchangers, the conduit apparatus comprising: a frame;first, second, and third supply conduits supported by the frame toconvey fluid to first, second, and third fluid circuits, respectively,wherein the first supply conduit is configured to convey fluid to thefirst fluid circuit for a heating load and the second supply conduit isconfigured to convey fluid to the second fluid circuit for a coolingload; first, second, and third return conduits supported by the frame toreceive fluid from the first, second, and third fluid circuits,respectively; and first, second, third, and fourth three-way valvessupported by the frame, wherein the first three-way valve is connectedto the first return conduit and the third return conduit, wherein thefirst three-way valve selectively regulates flow of fluid from the firstreturn conduit and the third return conduit to the first heat exchanger,the second three-way valve is connected to the first supply conduit andthe third supply conduit, wherein the second three-way valve selectivelyregulates flow of fluid from the first heat exchanger to the firstsupply conduit and the third supply conduit for selective distributionto the first fluid circuit and the third fluid circuit, the thirdthree-way valve is connected to the second return conduit and the thirdreturn conduit, wherein the third three-way valve selectively regulatesflow of fluid from the second return conduit and the third returnconduit to the second heat exchanger, and the fourth three-way valve isconnected to the second supply conduit and the third supply conduit,wherein the fourth three-way valve selectively regulates flow of fluidfrom the second heat exchanger to the second supply conduit and thethird supply conduit for selective distribution to the second fluidcircuit and the third fluid circuit.
 14. The modular conduit and valveapparatus of claim 13, including a controller configured to selectivelyregulate fluid flow by each of the first, second, third, and fourththree-way valves.
 15. The modular conduit and valve apparatus of claim13, wherein the third fluid circuit is a geothermal fluid circuit. 16.The modular conduit and valve apparatus of claim 13, including a firstinlet conduit connected to the first three-way valve and adapted toconvey fluid from the conduit apparatus to the first heat exchanger, afirst outlet conduit connected to the second three-way valve and adaptedto convey fluid from the first heat exchanger to the conduit apparatus,a second inlet conduit connected to the third three-way valve andadapted to convey fluid from the conduit apparatus to the second heatexchanger, and a second outlet conduit connected to the fourth three-wayvalve and adapted to convey fluid from the second heat exchanger to theconduit apparatus.
 17. A heating and cooling system, comprising: aheating/cooling apparatus having first and second heat exchangers; aconduit apparatus coupled to the heating/cooling apparatus and adaptedto be coupled to a plurality of fluid circuits for heating and/orcooling loads, the conduit apparatus positioned between theheating/cooling apparatus and the plurality of fluid circuits, theconduit apparatus comprising: first, second, and third supply conduitsto convey fluid to first, second, and source fluid circuits,respectively, wherein the first supply conduit is configured to conveyfluid to the first fluid circuit for a heating load and the secondsupply conduit is configured to convey fluid to the second fluid circuitfor a cooling load; first, second, and third return conduits to receivefluid from the first, second, and source fluid circuits, respectively;first, second, third, and fourth three-way valves, wherein the firstthree-way valve is connected to the first return conduit and the thirdreturn conduit to selectively regulate flow of fluid from the firstreturn conduit and the third return conduit to the first heat exchanger,the second three-way valve is connected to the first supply conduit andthe third supply conduit to selectively regulate flow of fluid from thefirst heat exchanger to the first supply conduit and the third supplyconduit for selective distribution to the first fluid circuit and thesource fluid circuit, the third three-way valve is connected to thesecond return conduit and the third return conduit to selectivelyregulate flow of fluid from the second return conduit and the thirdreturn conduit, to the second heat exchanger, and the fourth three-wayvalve is connected to the second supply conduit and the third supplyconduit to selectively regulate flow of fluid from the second heatexchanger to the second supply conduit and the third supply conduit forselective distribution to the second circuit and the source fluidcircuit.
 18. The heating and cooling system of claim 17, including acontroller configured to selectively regulate fluid flow by each of thefirst, second, third, and fourth three-way valves.
 19. The heating andcooling system of claim 17, wherein the heating/cooling apparatus is aheat pump, the first heat exchanger is a condenser, and the second heatexchanger is an evaporator.
 20. The heating and cooling system of claim17, wherein the conduit apparatus simultaneously conveys heated fluidvia the first supply conduit for use in the first fluid circuit andchilled fluid via the second fluid supply conduit for use in the secondfluid circuit.